thompson



- 5 Sheets--Sheet 1. H. G. THOMPSON. ROTARY STEAM ENGINE.

No. 6,962. Patented Deg 18, 1849..

5 SheetsSheet 2.

H. G. THOMPSON.

ROTARY STEAM ENGINE.

Patented Dec. 18, 1849.

5 Sheets-Sheet 8 H. G. THOMPSON.

ROTARY STEAM ENGINE.

No. 6,962. Patented Dec 18,1849.

5 Sheets-Sheet 4.

Patented Dec. 18, 1849.

H. G. THOMPSON. ROTARY STEAM ENGINE.

W/V/ 4a ZZZ 5 Sheets-Sheet 5,

H. G. THOMPSON.

ROTARY STEAM ENGINE. v

Patented Dec. 18, 1849.

' UNITE STATES 5 T OFFICE.

HENRY G. THOMPSON, OF NEW YORK, N. Y.

Specification of Letters Patent No. 6,962, dated December 18, 1849.

To all whom it may concern.

Be it known that I, HENRY GRAHAM THOMPSON, of the city, county, andState of New York, have invented certain new and useful Improvements inRotary Steam-Engine, and that the following is a full, clear, and exactdescription of the principle or character which distinguishes them fromall other things before known, and of the manner of making,constructing, and using the same, reference being had to the accompanying drawings, making part of this specification, in which Figure 1 is afront elevation; Fig. 2 an elevation of one end; Fig. 8 a verticalsection, passing through and parallel with the axis; Fig. 4 a crossvertical section; Figs. 5 and 6, enlarged sections representing thearrangement of cut-off valves; Fig. 7, face and edge view of one of thepacking rings with the steam stops; Fig. 8, outside face view of packingrings with sectional rings for forcing up the same; Fig. 9, enlargedcross section of packing ring and method of forcing up the same; andFig. 10, sections of steam stops.

The other sections will be referred to in their appropriate places.

The same letters indicate like parts in all the figures.

The engine to which my present improvements are applied is on thegeneral principle of the rotary engine, secured to me by Letters Patentsealed on the twenty-second day of August, one thousand eight hundredand forty-eight, in which the piston wheel rotates within a stationarycylinder, there being one more piston on the steam wheel than there aremovable steam stops or abutments.

The first part of my invention, which relates to the form of theperiphery of the piston wheel, and the mode of operating the steam stopsor abutments, consists in glving the required in and out motions to thesteam stops or abutments, by a crank motion for each, the crank arborsbeing rotated by a pinion or pinion wheels on each, engaging the cogs ofa cog wheel or wheels on the shaft of the steam wheel, when this iscombined with. a piston wheel, the periphery of Which is of a formgenerated by the motion of the steam stops or abutments, and therotation of the piston wheel, so that the edge of the steam stops,during the rotation of the piston wheel, shall be always in contact withthe periphery of the piston-wheel, and yet not operated by it.

The second part of my invention, which relates to the construction ofthe steam stops, consists in makin their ends with toes or projectionsextending down on each side of and embracing the sides of the pistonwheel, and fitted to grooves in packing rings, or in the inner faces ofthe cylinder, at the sides of the steam wheel, for the purpose ofpreventing the steam from passing around through the grooves in thepacking rings, &c. to the rear of the pistons.

The third part of my invention which relates to the method of governingthe induction of the steam to the cylinder, consists in combining withthe rotating steam piston wheel, cut off valves, operated by toes onrock shafts, receiving motion from eccentrics or their equivalents onthe crank shafts or arbors that operate the steam stops, that themotions of the valves may corre spond with the motions of thesteam-stops.

The fourth part of my invention consists in having a continuous orannular chamher, at the side of the steam cylinder, communicating withthe steam pipe, and also with the inside of the steam cylinder byappropriate ports, when this is combined with the cut-off valves placedwithin said chamber for regulating the admission of the steam. And thefifth part of my invention which relates to the method of packing theengine, consists in efiecting this end, by means of two metal rings, oneof the said rings being placed on each side of the steam piston wheeland between it and the cylinder heads, and forced up by rings ofmetallic rubber, the said metal rings being grooved radially to receivethe ends of the steam stops or abutments, and with holes correspondingwith the steam and exhaust ports, whereby I am enabled by the said tworings, to pack the steam piston wheel, the steam and exhaust ports, andthe ends of the steam stops or abutments.

In the accompanying drawings (A) represents the steam wheel, mounted ona shaft (B) that has its bearings in an appropriate frame (C) of anydesired construction.

The pistons (five in number, but which may be increased or decreased atpleasure) are projections from the circle of the wheel, of a formgenerated by the rotation of the wheel, and the in and out motions in aradial direction, of the steam stops, as will be hereinafter described.The pistons thus formed are provided with packing (a) at the parts ofgreatest projection from the center. The piston wheel is surrounded by acylinder (D) properly secured to the same frame, and its inner peripheryis accurately formed, that the pistons in their rotation by means of thepacking, may work therein steam tight. The heads (E, 13,) of the saidcylinder are secured by bolts (2)) to the flanches of the cylinder, andare each formed with an annular chamber, the one (0) constituting whatmay be termed the steam chest, and the other (0) a continuation of theexhaust pipe. These annular chambers should be in diameter about equalto the diameter of the steam-chamber, surrounding the piston-wheel, andthey may be made by casting them in the cylinder heads, or in separaterings interposed between the ends of the cylinder and the outer heads,and there secured by the bolts which secure the heads to the cylinder. 7

The steam ports (cl) for the admission of the steam into the cylinder,are formed through the inner face of the chamber (0) and the exhaustports (cl) through the corresponding face of the other. The steam andthe exhaust pipes (F and G) should be so connected as to admit ofintroducing the steam in the annular chamber (0) and making the other(0) the exhaust for the purpose of reversing the engine; but as thismakes no part of my present invention, and will be understood by anycompetent engineer, it has not been deemed essential to represent anarrangement for this purpose in the drawings.

Within the annular chamber or steamchest (0) are partitions (e e) whichcut ofi the connection of each of the steam ports (cl) from the body ofthe chamber, and these partitions are pierced with ports made with valveseats to receive balance puppet valves (7 f) attached, each set to avalve rod (g), the upper end of which works in a hole made in thecylinder head, and surrounded by a helical spring (h) to insure thedescent of the valves, and the lower end passing through the innerperiphery of the annular chamber to the outside of the cylinder head,and is there properly formed to be acted upon by a long toe (i) on arock shaft so that when the shaft rocks, the valves are either opened orclosed to admit or shut off the steam.

The arrangement for operating the rock shafts will be hereafterdescribed.

There are four steam stops (H), that pass through radial apertures inthe cylinder (if the number of pistons be increased or decreased, thenumber of stops must also be increased or decreased, but the number ofstops must always be one less), with their inner edge made with elasticor other pack ing, adapted to the surface of the pistons, that as they(the pistons) rotate, and the stops move in and out, the surfaces mayalways be in contact and steam tight. The stops are made of greaterlength than the piston wheel, and at (K, K,), they are formed withprojecting toes which embrace the ends of the pistons, and always extendwithin the periphery of the piston wheel; and the ends, as well as theprojecting toes of the stops, are adapted to slide in recesses (Z) madein a packing ring of metal (J), which is interposed between each end ofthe piston wheel, and the annular chamber (0 c) the said rings beingalso provided with holes and (m) corresponding with the steam andexhaust ports. Between each ring and each of the heads, are twosectional metal rings (n, n,) which, in their cross section, are wedgeformed in opposite directions, and fitted to corresponding. recesses inthe heads. The space between these two rings is also wedge-formed toreceive a flanch (0) of a corresponding form, on the face of a sectionalring (p), and back of this ring is a sectional ring (g) of metallicrubber (but for which other elastic substance may be substituted) fittedto a recess in the cylinder head, that the tension of the said rubberring in forcing the ring (p) in- Ward, shall force the two rings (a, n,)apart,

one inward and the other outward, and these, by their wedge form, pressthe ring (J) against the face of the wheel. The same arrangement is madeon each side. In this way, when the heads of the cylinder are screwed upto their places, the ends of the piston-wheel, the steam and exhaustports, and the ends of the steam ports will be completely packed by thetwo rings of metal, and the extension of the toes of the steam stopswithin the periphery of the piston wheel, Will effectually prevent thepassage of the steam from one side of the pistons to the other, throughthe recesses of the packing rings, in which the ends of the steam stopswork. Outside of the cylinder, the steam stops are secured each to thecross head (11 which slides in appropriate ways (0'), and which has ateither end a connecting rod (79) that take hold of cranks q) in shortarbors (r, 9') one on each side, the said arbors having their bearingsin brackets secured to the cylinder heads. And on each arbor (7"), thereis a pinion (s), the cogs of which engage the cogs of a wheel (I) on themain shaft (B), the diameter of the cog wheel being as many times largerthan the pinions, as there are pistons on the piston wheel, so that eachpinion shall rotate, and with it the crank that operates the steam stopconnected therewith, as many times for each rotation of the piston wheelas there are pistons on the wheel, that each steam stop may be moved inand out for the passage of each piston. And, as the periphery of thepiston wheel is generated by its rotation, and an in and out radialmotion corresponding with the motions of the steamstops, it follows, asa consequence that if the parts are accurately fitted and proportioned,that, as the piston wheel rotates, the steam stops will move in and out,and continue in contact with the periphery thereof, and yet not beoperated thereby, so that the only friction between the periphery of thepiston wheel and the steam stops will be due to the elasticity andpressure of the packing interposed.

As the cross-heads of the steam stops have connecting rods attached ateach end, there must be a corresponding arrangement of cranks, crankarbors, pinions and cogwheel at each end of the cylinder, this beingessential to the proper working of the steam stops, although it may beeffected by an arrangement at one end only, but in a less perfectmanner. At the end of the engine, where the balance valves are situated,the crank arbors (r) are each provided with an eccentric (t) andconnecting rod (to), which takes hold of the arm of that rock shaft,which operates the balance valves that govern the steam port by the sideof the corresponding steam stop. The position of the eccentric,relatively to the crank, must be such that as each piston passes any oneof the several steam stops, the balance valves shall be open, that asthe piston passes the port next to the stop, the steam may enter thecylinder, and when the piston has made a given portion of its motiontoward the nextstop, that the valves may descend to cut off the steam,and permit the steam within to act expansively. In this way, by varyingthe relative positions of the eccentric and crank, the valves can bemade to cut off the steam, at any portion of the pistons motion betweenthe several stops.

WVhen the engine is reversed, the periods of the opening of the cut-offvalves will be amply suflicient for the steam to exhaust, particularlyas the full power of the engine is but seldom required for the reversemotion.

Although I have described the use of balance puppet valves for governingthe admission of steam to the cylinder, I do not wish to confine myselfto the use of such valves, as single puppet or slide valves may besubstituted, without changing the principle of my invention; and I haveonly described and represented balance puppet valves for the reason,that, in my judgment, they are the best adapted to the purposecontemplated by me.

Having thus described the principles or characteristics of myinventions, which distinguish them from all other things before knownand described; and represented the mannerof constructing and using thesame, and some of the modifications of which it is susceptible, what Iclaim as my invention, and desire to secure by Letters Patent, is-

1. The method of operating the steam stops or abutments, by a crankmotion derived from the rotation of the piston wheel, substantially asdescribed, when this is combined with the rotating piston wheel, theform of the periphery of which is such as would be generated by itsrotation and the motions of the steam stops, substantially as described,that the steam stops may always in their motions, be in contact with theperiphery of the piston wheel, and not operated by such periphery, asdescribed.

2. I claim making the ends of the steam stops with projections or toesthat embrace the sides of the piston wheel, and extend within theperiphery thereof, substantially as described, when this is combinedwith the grooves or recesses in the packing ring, or any equivalentsubstitute therefor, substantially as described, whereby the steam isprevented from passing from one side to the other of the pistons,through the grooves or recesses in which the ends of the stops slide, asdescribed.

3. I also claim, in combination with the herein described method ofoperating the steam stops the employment of cut-off valves, operated byeccentrics (or their equivalents) on the crank arbors that operate thesteam stops, substantially as described.

HENRY G. THOMPSON. Witnesses:

REUNE MARTIN, JEssE PAYNE, Jr.

